Evaluation of two in-house immunoenzymatic tests to serodiagnose subclinical paratuberculisis in a sheep flock in Mexicali valley, Mexico

ABSTRACT

Paratuberculosis (PTB) or Johne’s disease is a common ruminant infectious disease caused by Mycobacterium avium subsp. paratuberculosis (MAP). In this study, two MAP antigens were compared for their diagnostic utility to detect subclinical PTB in a sheep flock in Mexicali, Mexico. Sheep (n = 31) without clinical signs but positive on a direct fecal-polymerase chain reaction were tested with two preabsorbed in-house enzyme linked immunosorbent assays (ELISAs) using: (1) an ethanol-extracted surface lipid antigen (EVELISA) and (2) a protoplasmic antigen (ELISA-PPA). Sensitivities of the EVELISA and ELISA-PPA were 84% (95% CI; 66–95%) and 29% (95% CI; 14–48%), respectively. The EVELISA test could be a fast and effective way to identify subclinical ovine PTB for severely affected flocks.

KEYWORDS:

• Mycobacterium avium subsp. paratuberculosis
• Johne’s disease
• sheep
• ELISA
• EVELISA
• PPA

Acknowledgments

The authors are thankful to the Mexican Council for Science and Technology (CONACyT) for Graduate Student Fellowship to EPB and TCR.

Funding

This study was partially supported by a research grant from Autonomous University of Baja California (UABC, CA201/5/C/20/14, 201/5/C/3/18), and by Fundación Produce Baja California, A.C.

Additional information

Funding

This study was partially supported by a research grant from Autonomous University of Baja California (UABC, CA201/5/C/20/14, 201/5/C/3/18), and by Fundación Produce Baja California, A.C.